With the popularity of liquid crystal display and the continuous growing market, in many choices, the requirements of the users to the liquid crystal display devices are increased. For the conventional display, even the RGB three-color display with high color saturation, or even RGBY four primary monitors cannot meet the user's requirements for the color gamut coverage of the display.
In recent years, since the invention of the graphene light-emitting element, makes the graphene applications in the display area to be enlarged extension. Graphene has a hard, high transparency (transmittance ≈97.7%), high thermal conductivity (up to 5300 W/m·K), the high electron mobility rate (more than 15000 cm2/V·s), and other great properties. The applications in display are gradually increased in recent years, especially in the application of touch screen (as an alternative to the conventional transparent conductive film, ITO) and applications in LED area. By theoretical calculation, the color gamut of the graphene can reach 158%. But in the conventional technology, there is no method of how to achieve the high color gamut coverage.